There is a previously known technology of detecting the position or others of any object being in touch with or being in proximal to the display surface of a display device. This technology includes a typically and generally popular technology, which is about a display device provided with a touch panel.
The touch panel is also of various types, and the type being generally popular is to detect a capacitance. The panel of such a type is so configured as to detect the position or others of any object by sensing any change of the surface charge of the touch panel caused by a finger touch on the panel. Accordingly, using the touch panel of such a type allows a user's intuitive operation.
Herein, in Patent Literature 1 and Patent Literature 2, for example, the applicant of this application is proposing a display device provided with a display section (display-and-image-pickup panel), having a display function of image display and an image pickup function (detection function) of object image pickup (detection).